Extension-ladder



(No Model.)

\ G. W. H. MOULTON.

EXTENSION LADDER.

No. 556,830. Patented Mar. 24,1896.

UNITED STATES PATENT OFFICE.

CHARLES V. II. MOULTON, OF CAMBRIDGE, MASSACHUSETTS.

EXTENSION-LADDER.

SPECIFICATION forming part of Letters Patent N 0. 556,830, dated March24, 1896.

Application filed May 23, 1894. fierial No. 612,196. (No model.)

T0 66 whom it may concern.-

Be it known that 1, CHARLES \V. H. MOUL- TON, of Cambridge, in thecounty of Middlesex and State of Massachusetts, have invented a new anduseful Improvement in Extension- Ladders, which will, in connection withthe accompanying drawings, be hereinafter fully described andspecifically defined in the appended claim.

Insaid drawings, Figure 1 is a side elevation of a portion of the sideof the top section of an extension-ladder and the pawl thereto securedby which said section is supported upon the lower section. Fig. 2 is across-section taken on line a: 1 Fig. 1.

This invention relates to the means by which the upper or slidingsection of an extensionladder is held in position upon the lower sectionof the ladder; and it consists in the means by which the pawl is pivotedupon the ladder side, so that it can always turn readily upon thepivot-bolt by which it is held in place, as will be herein described,and then defined in the appended claim.

Referring again to said drawings, A represents the ladder side, and B isthe pawl, which engages the rungs of the lower section of the ladder,(Not shown.) Said pawl is the selfacting kind-that is, it is notactuated by springs, but by being so exactly adjusted in its weight uponthe opposite sides of its pivotbolt as to act automatically by its ownweight. In order that said pawl shall move upon its said pivot-bolt gwith the least possible friction, it is requisite that it bear thereonat a small point and that said bolt shall not compress it against sideA. To effect the first of these results, the hole a through said pawl isenlarged from its center outwardly on each side, as shown clearly inFig. 2, so that said pawl bears upon said bolt only at the center of thepawl, and it is held steady and true between bolt-head d and side A, thelarger surface of the latter affording a broad support for said pawl;and in order that nut 79, screwthreaded on said bolt, can be turned uptight and snug and yet not pinch said pawl a rivet 0 passes through sideA and bolt g, so that said bolt cannot be drawn inward by the action ofits nut beyond the intended limit, as already explained. It will thus beseen that pawl B can revolve on bolt 9 with but a minimum of friction,which is at the center of its plane, and that said pawl can be held justas near to side A as desired, and yet the nut I) cannot by anycarelessness in turning it up so pinch said pawl as to interfere withits revolving freely on its pivot-bolt.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is

The combination of ladder side A, the pawl B, its pivot-bolt 9 providedwith head d and nut b, and a rivet a passing through side A and saidbolt g so that said bolt by the action of its nut cannot pinch said pawlbetween side A and head d to prevent free rotation of the pawl, asspecified.

CHARLES W. H. MOULTON.

Witnesses T. V. PORTER, M. E. Bownrron.

